System of mining oil shales



July 25, 1933- s.` N. KARRlcK 1,919,636

SYSTEM OF MINING OIL SHALES Filed March 5, 1930 l 5 Sheets-Sheet lOuf/e115 DUUDDDUUED l July 25, 1933. s. N. KARRICK SYSTEM OF MINING OILSHALES Filed March 5, 1950 5 Sheets-Sheet 2 July 25, 1933. sf N, KARRlCK1,919,636

SYSTEM OF MINING OIL SHALES Filed March 5, 1930 5 Sheets-Sheet 4 l//ce7nne (J1/Wenko@ July 25, 1933. n s, N KARRICK 1,919,636

SYSTEM OF MINING OIL SHALES Filed March 5, 195o 5 sheds-sheet 5 NUMBUPEMI Patented July 25, 1933 c SAMUEL N. KABRICK, OF BLT'IMOBE, MARYLANDSYSTEM or'nmme'on. slums Application filed March 5, 1980. Serial No.438,385.

This. invention relates to the production gases "with nitrogen vandcarbon dioxide of oil from shales or coals andv particularly concernsnew methods `of developing the oil shale deposits and'treati-ng theoil-forming materials underground. By my methods of operation'shale oilsand fuel gases may beV produced at a fraction of the costs which must bemet by other methods.

The large deposits of oil shales `of the United States occurring inColorado, Utah and Wyoming, also in Indiana and Kentucky, containcontiguous strata of oil shales ranging from twenty-five to one hundredfeet in thickness which may be distilled successfully by my method.Also'in Utal there are large deposits of suitable co'als for thistreatment.

I have worked out improved mining methods for preparing the deposits for'20 treatment which take advantage of certain natural features of thedeposits, namely, structure, thickness, type of material and heightabove the valley ioors, etc., tol obtain great economies 'in thecommercial treating of the shales and handling of the products formed. For example, 'in the oil shale areas of Colorado the richest oilgnshalesare 0btained within a series of strata some fifty feet thick lyingapproximately 1500 feet above the valley ioors and toward the top of aprecipitous face some 500 feet in height (see Fig. 1). The methods Iprefer to use are hereinafter described in relation-to .these beds ofshales, but are not limited thereto, nor in the precise form as shownand described.

In order to supply the necessary heat for carrying on the distillation,I introduce into contact with the shale the products of combustion fromburning variable mixtures of the combustible gas formed in distillingshales. The temperature produced is governed by regulating the amountand proportions of the gas and air used and will be such 45 that thevolatiles are removed from the shales and the carbon residue remainingin the spent shale is heated suliiciently high to form producer gas byinteraction with the products of combustion. In this way I am able toprevent excessive dilution of the shale which would render the gases ofno value for fuel purposes. Additional fuel gas is also formed byintroducing air alone into contact with the hot spent shale after theoils are removed by which the residual carbon is slowly burned andtransformed into producer as. The two sources of gas provide a supp y'ofgaseous fuel which will be a surplus over that required for thedistillation of the shale and will leave ample for generat- 1ng power bygas engines or steam plant to run fans, air compressors, pumps, dynamos,etc., for the entire shale works, refinery and camp uses.

In applying my method of mining and 'distillation to the-oilfshales ofColorado in the bodies referred to above, I produce large bodies of lumpoil shale either in the form of vertical chambers or tunnels which aresubstantially full of the broken shale.v Only enough of the shale isremoved to allow for the normal voidage of the broken shale left in thechambers. The hot gases are then passed either downward or upward throuh the chambers, or horizontally through t e tunnels. The chambers occupynearly the full height, or thickness, of theseries of strata se ected asmost advantageous to treat and are separated by partition walls of oil8o shale of the minimum thickness that will preserve agas-tight'separation of the chambers and yet of such minimum thiclmessthat the oil shale forming the walls will be distilled simultaneouslywith the broken shale occupying the chambers.

In the above case I prefer to develop the shale deposit by using closelyspaced vertical or sloping chambers or raises about 50 feet in height.4This stratigraphic height has been shown in the Bureau of Mines-investigations Ato contain a series of contiguous strata which are therichest in the oil shale measures and that they vary in oil field from20 to 65 gallons per ton of shale and the 50 95 feet will average 35gallons per ton. In one form of preferred developmentthe chambers willbe installed four in a unit on each side of and above a common servicetunnel to which they all are connected by a simple 10o broken materialto near t ing the adjacent chambers will not be broken through and willbe of proper thickness to permit complete distillation of theircontained oils. Y

The branch raises leading down from the bottom of the shale raises mustbe amply" steep to permit the broken rock or oil shale to run out freelyas the blastin proceeds during the development work. Since the branchralses lead down into the servicetunnel, I provide for placing mine carsunder the raises to receive the rock shot down and, thereby, I avoid anyhand loading of the development rock. The rock and oil shale that isremoved in'wthe development work will be from 25 to 40 percent of thetotal shale broke en and by my gravity method of transferring thematerial into hars I reduce the cost of development to a minimum.

The oil shale removed from the raises is trammed to another part of themine and dumped through a hopper and gates in the f tunnel floor leadinginto a distilling shaft of several hundred feet in depth. This materialis separately distilled and gasilied by the same method as used in thevertical chambers referred to above.

It will be recognized from this general description that all the shaleis treated underground in substantiall vertical shafts or. chamberswithout requlring any excavating or loading either by hand or by poweroperated machinery. f Also, both quantities of shale, namely, thattreated in place and that removed and dumped into the distilling shafts,are subjected to the downward flow of hot gases which effects thedistillation of the large and small lump material and subsequentlyconverts much of the residual car bon of the shale into producer gas.

When the distillation and gasification treatment of the shale in thevertical chambers is completed, the supplies of gas and air are cut oif,but no veffort is made to remove. the spent shale or make further use ofthe chambers. However, when ,the treat-l ments of the shale in theshafts are completed, the spent material is removed by bottom dischargegates and a fresh charge is substituted and the treatments repeated. Theshafts thereby serve for continuous use and Atheir construction cost,which is very low, is

nevertheless charged oif in treating many` charges of oil shale. l Byreference to Fig. 1,

it will be observed that the discharge gates 0f the distilling shafts4are so located that ample dump room is'provided for the spent shale.

The various mining methods I apply are well known and the varioustreating galleries are. modifications of forms of hard rock workingswith which I have had experience in Utah and Nevada, but are hereinadapted and improved upon to make possible the economical treating o thelarge deposits of oil shales, all of which methods and forms comprise myinvention.

In order to make more clear the details of m invention and the forms inwhich it may e applied, reference is now made to the drawings formingpart of this application.

IFigure 1' is a vertical section through a Fig. 7 is a plan view of theworkings shown in Fig. 6. Figs. 8 and 9 areenlarged verti cal sectionsat right angles to each other through the treating tunnels of Figs. 6and 7. Fig`` 10 is a vertical, longitudinal section, like in ig. 8, butin addition shows some detail of the caving method. '1 is the rockoverburden lying on top of the strata of oil shale to be worked. 2 is aseries of strata of oil shale which are to be worked as a body. 3 is thecountry rock lying below the main body of rich oil shale.

4 is a service tunnel approximately 30 feet below the bottom ofthe oilshale. This tunnel is driven in a stratum of fairly rich oil shale whichoccurs at this position. 5 are vertical chambers filled-With broken oilshale and, as shown, are nested together'y within the strata of pay oilshale. 6 are series of sloping branch raises which connect with thebottom of the vertical chambers and with the service tunnel 4.

7 is a vertical or inclined shaft extending downwardly several hundredfeet from service tunnel 4. At the bottom of shaft 7 is located agas-tight gate 8. Below this gate is a chute 9 by which the materialdischarged from the shaft is deposited on the dump below the escarpmentof the mesa. Near the top of the shaft 7 is a gas-tight gate l0- throughwhich the oil shale mined from theA chambers 5 is deposited into theshaft. Be-' low the gate 10 are connected a gaspipe 1l and air pipe 12through which the combfstible gaseous mixture is introduced fordisremesa the shale] are removed and conducted, to the condensers '(notshown). 14 is also .a vapor and gas outlet by which the volatileproductsy from the chambers 5 are conducted from the mine to thecondensers. ^On the outer end of connection 14 is shown an explosiondoor which is provided as va safety measure to obviate damage to thecondensing plant in the event of mild explosions occurring within thegas tunnel.

Fig; 2 is a plan view of the workings shown in F ig'. 1 and in additionshows the present and future development areas, also a reserveshalearea. The gases and vapors coming from chambers 5 pass out oftunnel 4 by way of )connection 14. A gas barrier 16 in tunnel 4 is shownat the extreme right of the zone occupied by chambers 5 and serves toprevent the explosive gases and vaporsfrom entering the tunnels 4 Thetunnels 4 are used for transportation, communicationfetc.,

. and haulage of the shale for distillation in shaft 7. The barrier 16is advanced to the right as neufchambers are made ready for use. By thisarrangement one system of tunpart of Fig. 3 are shown thepreliminarysmall raises which are driven up through the body of oilshale. The shale removed from this operation is deposited in thedistilling shafts 7. In dotted lines is shown a plan view of the systemof branch raises by which the chambers 5 are connected with thetunnel'4.

Fig. 4 is a section in large scale of the vertical chambers and theirconnections with the tunnel 4. 2 is the body of oil shale and 3 is thecountry rocklying immediately below. An end View is also shown ofthe'service tunnel which passes through a stratum of medium rich oilshale.

In preparing to develop the chambers 5,

I first install the connecting raises 6 leading`from the tunnel 4 up tothe base of the rich oil shale strata. The direction of theconnectingraises is so governed that the vertical chambers 5 will beproperly spaced from each other. Next the small raises 5 are installedand' are made to connect with the tops of the branch raises 6 and extendto approximately the top ofthe rich oil shale strata. The raises are nowready for filling with the broken shale ,which is derived by drillingand blasting the surrounding walls of the raises 5. It is essential thatcare be exercised in this step of the process in order to produce therequired amount of broken sha e to fill the chambers with the minimumexpenditure of owder while at the same time reventing reakin through thewalls into e adjoinlng cham rs. In order that the chambers 5 will befilled with broken Y shale by the blasting procedure, it is necessarythat the volume of the raises 5 shall be approximately 25 to 35 percentof the volume of the chambers' 5. With this in mind the spacing of thechambers is so laid out that the walls 17 between the various chamberswill be of substantially uniform thickness and approximately twice thediameter of the large ,lumps of broken shale in the chambers. By thisarrangeme t and method of development I am able t effect thedistillation of the shale rock of the Walls simultaneously with thebrokenshalewithin the chambers. I thereby make possible the extractionof the oils from much more of the shale rock than is actually mined.

Fig. 5 is a vertical section taken at right angles to Fig. 4 along theline 5 5. The chambers 5 are full of broken shale and are ready tocommence the distillation of their A contained oil. The heat Vforcarrying on the distillation is herein shown as being supplied by aburning mixture of gas and air introduced by pipes 18 and 19 leadinginto each of the chambers at the tops. The air and gas are deliverelthrough the tunnel 4 bypressureA mains 20 and 21. Connections are. madewith the mains by pipes leading up through the raises 5 of the newgalleries undergoin development, as shown at the extreme right.Regulating valves`22 and 23 are used to adjust the flow of air and gasinto the various chambers. I may also use gas burners set intothechamber walls and connected to the gas and. air pipes 18 and 19.

In order to determine when the distillation is completed in therespective chambers I .provide gas sampling pipes 24 which extend :fromtunnel 4 well up into each of the branch raises. The lower end of thesampling pipes 24 extend through thegas-tight bulkhead 16 and areprovided at their outer end with suitable valves. To determine theprogress of distillation of any chamber, a sample of rthe volatileproductsproduced therein is drawn through the gas sampling pipe andanalyzed for the percentage of oil vapors, carbon dioxide, oxygen, etc.,contained. The amountrof one or more of the above `ingredients willindicate to an experienced operator the progress of the distillation orgasification and the adjustments, if any, that should be' made. vThegas-tight bulkhead 16 is satis- A.Iliactorily made of angle iron postscovered with .metal `lath and plastered over with cement mortar. When anew set of eight chambers are ready for operating a newbulkhead iserected to correspond as to location with the one herein illustrated,following which the present one is removed. This can be done by use. ofa cable connection operated from the other side of the new bulkhead.

Figs. 6 and 7 are similarto the` Vertical section and pian illustratedin Figs. 1 and 2. However, instead of using vertical cham bers andbranch raises, I show a modified method of development in which largeparallel tunnels 25 filled with large lumps of broken shale are used. Asdescribed above, in relation to the vertical chamber method, it isnecessary to remove approximately 25 to 35 per cent of the shale fromthe distilling tunnels in order to provide the voldage in the mass ofbrokenshale that fills the tunnels. The removed shale will, as abovedescribed, be treated in the underground shafts 7 shown in Fig. 7. Amethod is provided for supplying the heat to the distilling shale byburning air and gas which are supplied through pipes 26 and 27 passingalong the service tunnel 4. The gases and vapors evolved in the chambersare removed by gas outlet tunnel 28. This tunnel will likewise serveboth as a transportation and later as a gas outlet tunnel. The tunnel 4will permanently serve as a service and haulage tunnel. Tunnel 4branches off from tunnel 4 and leads to the vertical distilling shafts 7in which the mined shale is distilled.

Figs. 8 and 9 are vertical sections lengthwise and across the shaledistillingvtunnels shown in Figs. 6 and 7. ike numbers refer to likeparts. These tunnels as used to economically treat the thick oil shalebeds 1n Utah and Colorado may be approximately 2O to 40 feet wide by 50feet high and one hundred or more feet long. The oil shale is preparedfor distilling by first driving a long development tunnel the fulllength of the distillingntunnel and having a cross section of propersize to provide the voidage .between the blocks of oil shale that willfill the distilling tunnel when the treatment is under way; this shouldbe approximately 25 to T' 35 percent of the cross section of thedistilling tunnel.

The driving of the development tunnel is best shown in Fig. 10 and willbe by the usual up-to-date tunnelling methods wherein power loadingmachines will be used to remove the broken shale andcare will be eX-ercised to save powder and produce the minimum of fines. away and dumpedthrough the gas-tight doors into the distilling shafts 7 where it istreated by passing hot combustion gases from burning gas down throughthe charge.

Next holes 31 are drilled into the roof of the development tunnel' andof such depth and spacing that when the powder charges The broken shaleis trammed 'are fired the roof shale will be broken down in large blocks29 with the minimum production of fine material. Following this anotherround of holes are drilled and fired,

each round bringing the pile of broken shale nearer to the roof due tothe increase in volume of the brokenshale. The space between the brokenmaterial and the roof, just before the last round is fired, should besmall enough so that the broken shale after the last round is fired willremain touching the roof. This procedure prevents the formation of achannel over the charge by which route the hot distilling gases couldpass instead of through the charge. With blocks of shale averaging 2to'3 feet in minimum diameter, the time required4 to distill the lumpswill be possibly one hundred or more hours. The time required tocomplete the distillation from`end to end of the tunnel will depend onits length, but for tunnels of 100 feet .in length the time shouldlbeapproximately one week. s

This method of development has the disadvantage over the verticalchamber method described above in that the shale removed must be loadedby hand labor or power shovels into cars for haulage to the distillingshafts. However, the chambers are much larger and the shale can bebroken down into larger blocks by caving at very low cost, also theamount of-auxiliary development'work is somewhat less.

In Figs. 8, 9 and 10, numeral 4 is the` service and haulage drift. 26and 27 are respectively the air and fuel gas supply mains with branchesand valves leading through portals 30 into the distillation tunnels. 28is the gas and vapor outlet tunnel and 29 'the blocks of shale formingthe pervious charge. 31 are carefully spaced drill holes in the shaleroof.

After the blast-ing operations are completed and the tunnel is fullofblocks of shale, the gas and air pipes are run a short distance into thetunnels and the portals 30 sealed with masonry or concrete to form agas-tight closure. The closure should be reinforced slightly by crossrails or posts so as to provide the necessary strength to resistexplosions within the distilling tunnels.

By my method of underground treatment of oil shales or coals I may makefurther use of the chambers shown in Figs. l to 5 inclusive, to treatfurther quantitiesof lump carbonaceous materials. The material may bederived from other strata at higher elevations and charged into thechambers by chutes after removal of the spent charge. Also I do notlimit myself to the method shown in Fig. 5 for delivering fuel gas andair into the top of the chambers 5, but may prefer to drive servicetunnels above the chambers and introduce the gas and air by pipesleadingv through the tunnel.

I claim:

1. The method of obtaining oils and gases from carbonaceous materialcomprising driving passageways in the material in its natural position,depositing the carbonaceous material removed from the passageways Withinother passageways, made in the deposit wherein the shale is notsufficiently rich for independent working thereof, subjecting thematerial removed in the formation of the passageW-ays to the action ofheat at a carbonizable temperature to drive out the volatiles therefrom,subjecting the walls of the passageways to the action of heat at acarbonizable temperature to drive out the volatiles, and effecting acollection of gases and liquid products from the volatiles derived fromthe Walls and from the removed material.

2. The method of obtaining oils and gases from carbonaceous materialcomprising dr/iving passageways in the material in its natural positionand removing the material dislodged, enlarging the passageways bydislodging carbonaceous material from the walls thereof and therebye'ecting the formation of loose bodies of material filling thepassageways, subjecting the Walls of the passageways and the materialtherein to the action of heat at a carbonizable temperature to drive outthe volatiles, placing the removed material, other deposits containingshale insuiiiciently rich for independent work thereof and subjecting itto the action of heat at a carbonizable temperature, and effecting acollection of gases and liquid products from the volatiles.

3. The method of obtaining oils and gases from carbonaceous materialcomprising driving passageways in the material in its natural position,driving a shaft in the earth below the passageways, depositing theremoved material from the passageways in the shaft, enlarging thepassageways by dislodging carbonaceous material from the walls thereofand thereby eli'ecting the formation of loose bodies of material in thepassageways, subjecting the walls of the p-assageways and the materialtherein to the action of heat at a carbonizable temperature to drive outthe volatiles, subjecting the material in the shaft to the action ofheat at a carbonizable temperature to drive out the volatiles, andeffecting a collection of gases and liquid products from the volatiles.

SAMUEL N. KARRICK.

